iceweasel thinks it has java but websites disagree

[Ross Boylan <ross@biostat.ucsf.edu>]

I've encountered 2 different websites today that told me I need a java
plugin installed.  But iceweasel shows that it has such a plugin.

Can anyone suggest how I can diagnose or fix this?  The system is
basically lenny (including non-free and the Marillat archives).

For example, my schools VPN uses Juniper Networks and says
  You are using the secure gateway Java Session Manager, which requires
that your browser support:
      * Scripting of Java applets.
      * Microsoft Java 5.0.0.3802 (or above) or Sun Java 2 Runtime
        Environment 1.4.1 (or above).
You currently have the following version of Java installed on your
system: N/A

To download the latest version of Sun Java, go to http://www.java.com

My list of plugins show Java(TM) Plug-in 1.5.0_17-b-4


The other site with the complaint was for MS Live Meeting.
https://www112.livemeeting.com/cc/test2007/webJoin.  Oddly, that works
on one machine (the same one that got the previous error), but not
another.